I sorted out gearbox earth, was loose...
Cleaned with new washers, tight now.
Same with inner wing earths.

So many wires around the coil, wasn't sure what to do.

So you reckon power feed to coil, check this wire - any idea on colour?
Also run perm live from battery to this and give it a good run, see if it plays up.

Just need to find out what colour wire does what, and should be ok.
You any idea on colours?

Cheers mate